Oral Boards - OB

Risk of Major Aneuploidies in AMA

Risks of AMA

Maternal: HTN (2x >40), GDM (2-3x >40), CS/OVD, previa, abruption, labor dystocia, PPH, ICU, overall morbidity and mortality, SAB (2x), chromosomal abnormalities (2x >40), PPD, CVD

Fetal: Stillbirth (2x >40), LGA or SGA, PTB, low APGARs, NICU, hypoglycemia, multiples (?ART), but not really congenital anomalies

Management of AMA

>35: Counsel, LDA if another risk factor, first trimester US, offer genetic screening/testing, level 2 anatomy

>40: Third trimester GS, antenatal surveillance starting 32-36 weeks, delivery in 39th week

Baseline risk of a congenital or genetic anomaly in a pregnancy

2-3%

First trimester US/Serum Screening

Performed 10-13 weeks

Nuchal (11-14 weeks) + Pregnancy associated plasma protein A (PAPP-A) + bHCG

Detects 82-87% of T21

T21: Increased NT, low PAPP-A, high bHCG

T18: Increased NT, low PAPP-A, low bHCG

Second trimester serum screening

Performed at 15-22 weeks

AFP + bHCG + unconjugated estriol + inhibin A

Detects 81% T21

T21: Low AFP, high bHCG, low estriol, high inhibin A

T18: Low everything (inhibin A can be normal)

Open NT defect: High AFP (advantage over cfDNA)

cfDNA

Detects placental fragments starting at 9-10w, peak FF 10-21w

Highest sensitivity and lowest FP rate of all methods > now standard

T21 sens/spec >99%, T18/13 >90%

Cautions: Must confirm abnormal results with diagnostic test, PPV is lower in low-risk/young pts and for rare conditions, low FF (obesity, early GA, aneuploidies) can cause test failure or false results, expanded cfDNA has minimal validation

Carrier screening

ACOG: Offer to ALL pts (pregnant, TTC, considering), may decline

Includes CF, SMA, CBC, hemoglobinopathy testings

Ethnic-specific, pan-ethnic, or expanded also acceptable

Ancestry and family history based: Tay-Sachs (AJ, French-Canadian, Cajun), FX, hemoglobinopathies (African, Mediterranean, Southeast Asian, Middle Easter_, Ashkenazi expanded panel (Canavan, familial dysautonomia, Tay-Sachs

Invasive Diagnostic Testing

CVS: 10-13 weeks, samples chorionic villi, 98-99% accurate, 0.2% risk of pregnancy loss

Amniocentesis: >15 weeks (preferred unless earlier dx is needed), samples fetal cells in amniotic fluids, can also detect NT defects via AFP, 98-99% accurate, 0.05-0.1% risk of pregnancy loss

Can test karyotype, chromosomal microarray, FISH, gene panels, exam/genome sequencing

Don’t forget Rhogam!!

Discuss hemoglobinopathies vs thalassemias

Normal hemoglobin (HbA) has 2 alpha chains and 2 beta chains.

• Thalassemias are quantitative defects: reduced production of structurally normal globin chains.

• Structural hemoglobinopathies are qualitative defects: an amino acid substitution producing an abnormal globin chain.

• Both groups are autosomal recessive and can overlap clinically.

Lung Physiology in Pregnancy + Asthma

Normal: Increased minute ventilation, chronic compensated respiratory alkalosis, elevated diaphragm

Not normal: Decline in FEV1/FVC ratio

Spirometry (to measure FEV1) or peak flow monitoring can be used to distinguish between physiologic SOB and asthma worsening (q4-6 weeks)

Risks of Uncontrolled Asthma in Pregnancy

Poor outcomes are driven by poor control of asthma, not the presence of the disease itself. Active asthma management reduces risk of PTB, neonatal hospitalization, and GDM. Risk of PTB and low birth weight rises after just one hospitalization!

Maternal: HTN, GDM, PTL/PTB, CS, exacerbations requiring hospitalization, oral steroid effects, PPH

Fetal: SGA/FGR, PTB, perinatal mortality, neonatal respiratory distress/transient tachypnea, NICU, seizures, hypoglycemia

Medications for Asthma in Pregnancy

Mirrors non-pregnant treatment. Albuterol is SABA of choice, Budesonide is the ICS with the most historical safety data in pregnancy.

Asthma Exacerbation in Pregnancy

Treat aggressively!

• O2 with goal SpO2 >95%

• SABA ± ipratropium

• Early systemic corticosteroids

• IV or inhaled Mag in severe cases

• Hospital/ICU admission PRN

• Intubate PRN: Resp failure, “normal” or rising PaCO2 (resp alkalosis should be compensated in pregnancy), respiratory muscle fatigue, AMS, hemodynamic collapse

How to dose RhoGam

• Dose 300mcg at 28 weeks (not needed if paternity is known Rh neg)

• Postpartum:

  • If infant is Rh neg, do nothing

  • If infant is Rh pos > rosette test > if positive, quantify with KB

  • Give within 72 hours

  • 300mcg covers 30mL fetal whole blood (or 15mL fetal RBCs)

  • Volume of fetal blood = KB% x maternal blood volume (kg X 70)

  • 8 vials max

Management of BPP

0/10: Deliver

2/10: Deliver

4/10: Deliver if >32 weeks, maximize surveillance and prepare for delivery if <32w

6/10: Deliver if >36-37w, repeat in 24h if <36-37w

8/10: All good (unless oligo >36w, then deliver)

10/10: All good

RSV Immunization

• Only Pfizer vaccine is FDA approved in pregnancy

• Pregnant women 32.0 to 36.6

• Delivery not planned in next 2 weeks

• No prior vaccination in previous pregnancy

• RSV season 9/1-1/31

If no RSV vaccination in THIS pregnancy, baby should receive RSV mAb in their first flue season (first two seasons for high risk babies).

Cervical length screening and cerclage

Screening:

• No PTB: Universal screening at anatomy scan

• Prior PTB: q1-4 week screening from 16-24w

1. US-indicated: <25mm for prior PTB, <10mm for no prior PTB (can use VagP for 10-25mm with no prior PTB)

2. History-indicated: Prior cerclage or any second trimester loss attributed to cervical insufficient

3. Rescue/Exam-indicated: Painless cervical dilation with no labor/ROM/IAI/bleeding

4. Transabdominal cerclage: Prior failed vaginal cerclage or multiple 2T losses

Success rates: Elective 85-90% successful at preventing PTB/miscarriage, emergency 50-75% depending on multiple factors, TAC 90%

bASA for Pre-E prevention

Initiate between 12-28 weeks (ideally before 16w) and continue until delivery.

Give for 1 high-risk factor or 2 moderate-risk factors:

• Moderate: Nullip, obesity, fam hx pre-E, black race, low income, AMA, IVF, prior poor pregnancy outcome, prior FGR, prior PTB, >10y inter-pregnancy interval

• High: Hx pre-E, cHTN, multiples, pre-gestational DM, renal dz, autoimmune dz

Pre-Requisites for VAVD

• Fully dilated cervix

• Ruptured membranes

• Engaged fetal head

• Fetal head position is known

• Fetal weight assessment performed

• Pelvis is thought to be adequate

• Adequate maternal anesthesia

• Maternal bladder emptied

• Maternal consent after discussion of risks/benefits

• Ready to abandon attempt and proceed to CS if needed

Indications for VAVD

• Prolonged second stage

• Suspicion of immediate or impending fetal compromise

• Shortening of second stage for maternal benefit

How to perform VAVD

1. Ensure pre-requisites are met

2. Feel for posterior fontanelle

3. Place cup 2cm anterior to fontanelle

4. Ensure maternal tissue is excluded prior to engaging suction

5. Pull with maternal effort, following the curve of the pelvis (avoid rocking motions)

6. No set number of pulls or pop-offs, but descent should be noted within first few pulls

Risks of VAVD

Maternal: Should be compared to second stage, which is difficult to assess compared to risks of of second stage, but biggest one is OASIS injury.

Fetal: Scalp lac, subgaleal hemorrhage (between aponeurosis and periosteum, large volume, cross suture lines), cephalohematoma (between bones and periosteum, small volume, does not cross suture lines), intracranial hemorrhage, retinal hemorrhage, hyperbilirubinemia, NICU stay, brachial plexus injury

Counseling patients with breech babies

• 3-4% of all babies at term, most common frank breech (65-70%)

• Higher in septate/unicornuate/bicornuate uteri

• Perform position check at 36 weeks

• Options for delivery:

  • Planned vaginal delivery may be an option if they meets certain criteria, would need to be transferred to experienced provider. Possibly higher neonatal mortality than CS and higher short-term morbidity including low APGARs, intubation, and birth trauma (long-term outcomes less clear). Head entrapment is most feared complication.

  • ECV > VD is an option.

  • Planned primary CS has lowest neonatal mortality and short-term morbidity but higher risks for mom.

Criteria for breech vaginal delivery

1. GA >37 weeks

2. Must not be footling breech, other type OK

3. No fetal anomalies on ultrasound

4. EFW 2500-4000g with adequate maternal pelvis

5. Documented fetal head flexion

6. Adequate fluid (MVP >3)

7. No induction, spontaneous labor only with normal progress

8. Experienced provider and means for emergency CS if needed

How to perform breech delivery

1. Hands off the breech until umbilicus delivers, maternal expulsive effort drives delivery

2. Pinard maneuver (pressure on popliteal fossa) to deliver legs

3. Lovset maneuver (rotate fetal trunk, sweep arm) to deliver arms

4. Mariceau-Smellie-Veit maneuver with suprapubic pressure to flex chin and deliver head (or Pipers but I don’t do that)

5. If entrapment, consider Duhrssen incisions (2,6,10 o’clock), symphysiotomy, CS/abdominal rescue

Indications/Contraindications for ECV

Indication: All women with singletons who desire VD, >37 weeks in case of need for delivery

Absolute contraindications: Any situation in which VD is contraindicated.

Relative contraindications: Oligo/ROM, fetal anomaly, extended neck, FGR with abnormal dopplers, uterine malformation. Prior CS not a contraindication.

Success of ECV

50% successful ECV with 97% remaining cephalic at birth

Positive predictors: Multip, non-anterior placenta, abundant amniotic fluid, oblique lie, later GA, neuraxial anesthesia (NNT=5)

Negative predictors: High BMI

Risks and Benefits of ECV

Benefits: Reduces need for CS with no significant increase in maternal or fetal complications, cost-effective

Risks: Transient fetal bradycardia, abruption, PROM, cord accident, hemorrhage, PTL, need for emergency CS (0.2-0.7%, rare)

NYHA Heart Failure Classification

1. Mild/asymptomatic: No limitations

2. Mild: OK at rest, may have some impairment with activity

3. Moderate: OK at rest, but even light activity causes impairment

4. Severe: May be symptomatic at rest, no activity without symptoms

Indications for SBE PPX

• High risk patients at time of VD: Prosthetic valve, hx infective endocarditis, unprepared CHD, repaired CHD within 6 months or with residual defects, cardiac tx recipient with valvulopathy

• Also give for dental procedures. Not for CS.

• Regimens: Amox 2g PO or ampicillin 2g IV preferred. Cephalexin, azithromycin, clarithromycin, or doxycycline if PCN-allergic

Cervical cancer in pregnancy

• CIN3, CIS, or 1A1 cervical cancer (<3mm depth of invasion): Observe, repeat colpo q12-24 weeks in pregnancy (No ECC, biopsies with caution), VD OK

• If more advanced: Need Gyn Onc, CS recommended to prevent tearing/hemorrhage/tumor dissemination

FFN Testing

Rule out tool for imminent preterm labor

NPV: >99% for PTL within 14 days

PPV: 9-46%, low

Classifications of Congenital Heart Disease

• R>L shunt

  • Cyanotic

  • Deoxygenated blood bypasses the lungs or mixes with oxygenated blood, sending low-oxygen blood to the body, patients present with bluish tint

  • Examples: TOF, transposition of the great vessels, tricuspid atresia, pulmonary atresia, truncus arteriosus

• L>R shunt

  • Non-cyanotic

  • Oxygen-rich blood recirculates through the lungs or normal oxygen levels reach the body, keeping patients generally pink-skinned at baseline

  • Examples: ASD, VSD, AVSD, PDA

• Obstructive (no shunt)

  • Narrowing of heart valves or major blood vessels forces the heart to work much harder to pump blood

  • Examples: Coarctation, aortic/pulmonary stenosis

• Mixed/Complex

  • Incompatible with normal postnatal circulation

  • Great vessels or heart chambers are completely reversed or single-ventricle variants that require mixing of blood

  • Examples: Hypoplastic left heart, total anomalous pulmonary venous return, transposition of the great arteries

Causes of CHD

Genetic: Chromosomal abnormalities, single gene defects, inherited mutations, microdeletions

Maternal conditions: DM, PKU

Infections: Rubella, other infections/fevers

Substances: Teratogenic medications (lithium, isotretinoin, AEDs, ACE-i), alcohol, smoking/nicotine

Fetal Circulation

Neonatal Circulation

1hr and 3hr GTT

1hr: 50g glucose, non-fasting, cutoff 140 (if >190, auto GDM)

3hr: 100g, fasting, cutoffs 95/180/155/140 (Carpenter-Coustan), need 2 abnormal

2hr: 75g, fasting, done as one-stop-shop or postpartum to evaluate for ongoing DM

White Classification

A1, A2: Gestational DM

Other categories: Non-gestational DM, depending on factors such as age of onset, duration of disease, comorbidities (neuropathy, retinopathy, nephropathy), or need for organ transplant

Management of DM in pregnancy

Ultrasounds:

• T1DM, T2DM: Early anatomy and fetal echo

• GS q4 weeks from 28 weeks if normal

NSTs:

• T1DM, T2DM, poorly controlled GDM: 2x weekly NST at 32 weeks

• Well-controlled GDMA2: 1x weekly NST at 32 weeks

• GDMA1: Can consider past term

Delivery timing:

• GDMA1: 39.0 to 40.6

• GDMA2, well controlled: 39.0 to 39.6

• GDMA2, poorly controlled: Individualized, 36.0 to 37.6

• Pre-gestational, well controlled: 39.0 to 39.6

• Pre-gestational, poorly controlled or with comorbidity: 36.0 to 38.6

Workup and diagnosis of ICP

• Symptoms: Palms/soles pruritus, worse at night, no rash, jaundice uncommon

• Total serum bile acids: >10umol/L

• LFTs: Usually mild-moderate elevation

Severity of ICP

Low risk: 10-39

Moderate risk: 40-99

High risk: >100, this is where stillbirth rates rise exponentially

Treatment of ICP

UDCA 10-15mg/kg/day first line

Antenatal surveillance: Individualized, nothing reliably predicts IUFD in these pts

Low-moderate risk: Deliver 36.0 to 39.0

High risk: Deliver 36.0

Do not deliver preterm for clinical diagnosis without lab confirmation!

Liver disease in pregnancy DDX

ICP: 2nd tri onset, pruritus, elevated bile acids

HELLP: Usually 3rd tri onset

AFLP: Late 3rd tri onset, acute liver failure with hypoglycemia, hyperammonemia, and low plt/DIC

Treatment of DKA in Pregnancy

1. Continuous monitoring of mom and baby, hourly FS, q2-4h labs

2. Fluid resuscitation: 15-20cc/kg NS in the first hour, may need ½ normal based on corrected sodium levels

3. Potassium if needed:

   1. <3.3: Give K then insulin

   2. 3.3 to 5.2: Give K and insulin together

   3. >5.2: No K needed

4. Insulin drip, continue until anion gap closes

5. Add glucose when levels reach 200-250

6. Transition to SQ insulin 1-2 hours before discontinuing drip

7. Bicarb only with severe academia (pH <6.9)

Diagnosis of DVT/PE in pregnancy

1. Clinical assessment with YEARS criteria: Clinical signs of DVT, hemoptysis, whether PE is most likely diagnosis

2. D-Dimer: Cutoff 1000 if no YEARS criteria, 500 if at least 1 YEARS criteria

3. Start with compression duplex US > if positive, can skip to treatment

4. Chest imaging: CXR, then CTA if CXR abnormal or underlying pulmonary dz, V/Q scan if CXR normal

5. If clinical suspicion is high and evaluation is delayed or inconclusive, just treat

Treatment of DVT/PE in pregnancy

• Start immediately!

• Use therapeutic Lovenox (1mg/kg BID) or SQ heparin

  • Avoid DOACs, warfarin

• Continue through 6 weeks PP or at least 3 months, whichever comes second

• Can transition from Lovenox to heparin in third trimester for safer, more predictable window to discontinue in labor

  • Neuraxial OK after 12h ppnx and 24h therapeutic Lovenox > heparin 8 hours

• Severe / Life-Threatening Cases: For massive PEs or acute limb-threatening DVTs causing hemodynamic compromise, advanced interventions such as systemic thrombolysis, percutaneous thrombectomy, surgical thrombectomy, or ECMO may be required.

Intermittent Auscultation

• Used for low risk patients in spontaneous labor

• Lower CD rate but higher neonatal seizures, no change in perinatal death

• q15-30min in first/active stage and q5-15min in second stage

• Check for baseline and screen for decals around CTX > switch to cEFM if concern

ARRIVE trial

• IOL at 39.0 to 39.4 in nulliparous low risk women

• Decreased CS, decreased HTN, no difference in neonatal outcomes

Bishops Score

• Predicts the likeliness of VD within 24h

• Dilation, position, effacement, station, consistency

• Score 3-8: Consider cervical ripening prior to pitocin

Stages of labor and definitions

First stage: Onset of labor to full dilation, active phase starts at 6cm

• Prolonged latent phase may be defined as >16 hours, bur no evidence based definition (may be longer in IOL)

• Arrest of active phase: No progress with 4 hours of adequate UC or 6 hours of inadequate UC with pit

• Protracted labor: <1cm dilation in 2 hours

• Treatments: Pitocin, amniotomy, CS

Second stage: Pushing to delivery

• 2hrs of pushing in multip, or 3hrs for nullip

• Some definitions add 1 hour for epidural (shared decision making)

• Treatment: Manual rotation, OVD (97% success), CS

Failed IOL: Failure to reach active phase of labor (6cm with regular contractions) with 12-18 hours of pitocin after ROM

Methadone vs Buprenorphine

Risks of MJ in pregnancy

Maternal: gHTN and Pre-E, PTL/PTB

Fetal: FGR/low birth weight, risks of prematurity, long term developmental delay (including from breastmilk transmission)

Episiotomy

Risk factors for neonatal GBS infection

• Maternal GBS colonization

• No antibiotics in labor

• Prolonged ROM >18 hours

• Maternal fever

• Preterm GA

• Prior infant with GBS infection

Antibiotics for GBS ppx

GBS infection incidence 0.3-2% w/o abx, 0.1% with abx (3-4x risk reduction)

Regimens (need 4 hours for adequacy):

• Ampicillin 2g then 1g q4h

• Ancef 2g when 1g q8h (low risk PCN allergy)

• Clindamycin 900mg q8h, needs +clinda and +erythro sensitivity documented (high risk PCN allergy)

• Vancomycin pharmacy-dosed (not considered adequate by peds)

Who gets GBS ppx?

1. Any patient with positive screen (swab or bacteriuria)

2. Any patient with prior GBS infected neonate

3. Unknown GBS status and:

   1. Preterm

   2. ROM >18h

   3. Maternal fever

Grandmultiparity Risks

Grand-multip = 5 births >20w

Great-grand-multip= 10 births >20w

Maternal risks: PPH/atony, placental abnormalities, GDM, HTN, uterine rupture, hysterectomy, shock (tough to distinguish these from AMA)

Fetal risks: Macrosomia, low APGAR, PTL, IUFD, meconium

HSV in pregnancy

Valtrex (DNA chain termination/inhibition) dosing:

Primary: 1g BID x10 days

Secondary: Valtrex 500mg BID x3 days

PPX: Valtrex 500mg BID from 36w

CS if:

1. Active genital lesion or prodromal sx at time of labor/ROM/delivery

2. Primary outbreak within 6 weeks of delivery, even if lesions have healed

HIV in pregnancy

HA-ART (triple regimen) either started in pregnancy or continue prior regimen, goal VL=U

• Check VL every 2-4 weeks when adjusting dose or every 3m if stable

If VL <1000, ok for VD at term

If VL >1000, need CS around 38w + AZT

Also AZT for unknown VL, new dx in labor, adherence concerns

All babies need AZT

Breastfeeding generally OK with medication adherence and VL<50

Transmission <1% with adequate care

Transmission 15-40% without treatment, and additional 15-20% in breastfeeding

Causes of hydrops

Immune (10%)

• Rh incompatibility

• Other blood incompatabilities

Non-immune (90%)

• Genetic/chromosomal disorders

• Severe non-immune anemia

• Congenital infections

• TTTS

• Structural tumors of lung/liver

• Maternal factors (DM, SLE, hypothyroid)

Hypothyroidism in pregnancy

• Levothyroxine preferred

• Often need to increase 25-30% with UPT

• Goal TSH <2.5

• Check every 2-4 weeks in first half of pregnancy and at least 1 more time around 28 weeks

• Check 6w PP to titrate down

Hyperthyroidism in pregnancy

• 95% Graves disease

• Most neonates born to mothers with Graves’ disease are euthyroid.  Transient hypothyroidism occurs in 10 to 20% of newborns of treated mothers.  Transplacental passage of TSH receptor antibodies (TRAb's) causes hyperthyroidism in less than 5% of neonates.  Maternal thyroid levels at delivery do not accurately predict neonatal Graves' disease.

• PTU in first trimester

  • Can cause maternal hepatotoxicity, but methimazole can cause aplasia cutis and esophageal/choanal atresia in 1T

• Switch to methimazole for 2T-3T

• Monitor T4 levels every 2-4 weeks to ensure at/around ULN (~12)

Severe HTN meds

Give for sustained severe range BP over 15 min

Labetalol IV:

20/40/80/80 with 10min intervals > hydral

Max dose 220mg in 24h, hold for brady

Nifedipine IR PO:

10/20/40 with 20 min intervals

Hydralazine IV:

5/10/10 with 20min intervals > labetalol

Max dose 25mg in 24h, hold for brady

Mag and AEDs in pregnancy/eclampsia

PPH

Meds:

• Pitocin: 10-40U IV infused over 10-30min or 10UIM or 10U IU

• Misoprostol: 800-1000mcg PR

• TXA: 1g IV, can give 1 additional dose if needed

• Methergine: 0.2mg IM q2-4h, avoid with HTN

• Hemabate: 0.25mg IM q15-90min, max 8 doses, avoid with asthma

Procedures: Uterine massage, manual evacuation, JADA, Bakri, B-Lynch, UAE, hysterectomy, blood transfusion

HepB in pregnancy

• Test all pts for HepBsAg

• Test for immunity in all pts without documented immunity or vaccination

• Vaccinate in pregnancy if non-immune or grey zone (0,1,6 mo for Enegrix) - after 2 series, non-responder

• Use anti-virals (tenofovir) to reduce viral load:

  • If HBeAg neg: Treat for maternal benefit if VL >2K and ALT >2x ULN

  • If HBeAg pos: Treat for maternal benefit if VL >200K and ALT >2x ULN

  • For reduction of vertical transmission, treat any pt with VL >200K

• No evidence for avoiding invasive procedures or CS

• Babies born to positive/unknown moms should get HepB IG and vaccine within 12 hours

• No contraindication to breastfeeding

HepC in pregnancy

• Screen all pts for HepCAb, reflex PCR if positive

• No treatment in pregnancy, start after breastfeeding is completed

• No interventions to reduce transmissions

Validated Mental Health Questionnaires

• PHQ-2, PHQ-9

• EDPS

  • 10-14 mild, 15-19 mod, >19 severe

  • Anxiety: score of 5 or higher on the 3 anxiety Qs

• GAD-7

• MDQ to screen for bipolar

Mental Health Pharmacotherapy

• Anxiety/Depression: First line SSRI (sertraline, escitalopram)

  • Neonatal risks: Persistent pulmonary hypertension (0.5-1% risk but 10-20% fatal), neonatal adaptation syndrome (10-30%)

  • Monitor for response with validated scale

  • Always screen for BPD before starting SSRI

• PP psychosis

  • Very high risk with BPD

  • Prevention strategies: PP sertraline, PP lithium, sleep preservation

  • High transfer of lithium in breastmilk, not contraindicated but needs close monitoring

  • Acute: Haloperidol, olanzapine > call psych

• Severe PPD: Zuranolone

  • For onset in 3T or within 4 weeks PP

  • 2 week course

  • Can take with other SSRIs, SNRIs

  • Need contraception for 7 days after

  • Does pass into breast milk with low RID (<1) but no data on safety, consider pump and dump

  • Brexanalone no longer available

Differential for severe headache in pregnancy

• Tension

• Migraine

• Cluster

• Pre-E with SF

• PRES (posterior reversible encephalopathy syndrome)

  • MRI shows occipital cerebral edema

  • Look for headache, vomiting, AMS, blurred vision, seizure

  • Lower BP, treat Pre-E, deliver, call neuro

• RCVS (reversible encephalopathy vasoconstriction syndrome)

  • Abnormal CT angiography with diffuse segmental constrictions

  • Look for sudden headache, transient blindness, confusion, rapid improvement PP

  • Deliver!

• CVST (central venous sinus thrombosis)

  • Can be in 3T or PP

  • Look for nonspecific headache with focal deficit and seizure

  • MRI venogram

  • Give heparin

  • Workup for thrombophilia and APLS

• Epidural puncture headache

• IIH

• Intracranial hemorrhages/stroke

Who gets special anatomy scans?

• Nuchal (11-14w): Generally offered to everyone, but esp if not doing cfDNA

• Early anatomy (12-14w): Previous anomaly, sus current anomaly, AMA, DM, IVF, multiples, teratogens, enlarged nuchal, positive screening (cfDNA), BMI >30, abnormal placentation/implantation

• Level 2 anatomy: Same as early anatomy + GDM

• Fetal echo: Sus CHD, other anomalies, abnormal NT, genetic/chromosomal dx. multiples, pre-gestational DM, autoimmune, PKU, maternal infections, teratogen exposure, fam hx CHD

Antibiotics for wound/breast infections

CS infection:

• Mild/superficial: Augmentin, keflex, clinda

• Severe: Ancef, Vanc, Flagyl

• Deep/abscess: Open, drain, pack + ABX

Perineal wound breakdown:

• Mild: Augmentin, clinda, keflex/flagyl

• Severe: IV ABX (cefotetan, cefoxitin)

• Let heal by secondary intention!

Mastitis:

• Mild: Dicloxacillin, keflex, clinda, Bactrim

• Severe: Nafcillin, ancef, vancomycin

• Abscess: Drain

How does the KB work?

The principle behind the Kleihauer-Betke test relies on the acid resistance of fetal hemoglobin (HbF) compared to adult hemoglobin (HbA). When a maternal blood smear is exposed to an acid solution, adult hemoglobin washes out of the cells, while fetal hemoglobin remains trapped inside, allowing fetal cells to stain dark pink and stand out under a microscope.

When can you skip RhoGAM?

• Rh pos pt

• Confirmed Rh neg father

• Mom is already sensitized

• Severe allergy

• IgA deficiency

• Under <12 weeks (debatable)

Direct vs Indirect Coombs testing

Direct: Detects Abs already attached to the RBC

Indirect: Detects free-floating Abs (this is what we use in a maternal Ab screen)

Hemolytic Disease of the Fetus and Newborn (HDFN)

1. Maternal IgG crosses placenta and binds fetal RBCs

2. Hemolysis

3. Anemia

4. Causes extramedullary hematopoiesis, high output cardiac failure, and immune hydrops (ascites, pericardial effusion, pleural effusion, edema)

5. Post-natally, causes hyperbilirubinemia and kernicterus

Comparison of Abs that can cause HDFN

• RhD: Most common, only preventable cause, 16-17%>1% with Rhogam

• Kell (anti-K): Extremely severe, anemia out of proportion to titers (must monitor MCA Dopplers), also suppresses erythropoeises

• Rhc, RhE: Manage like RhD

• ABO incompatibility: Can occur in primps due to preformed Abs, usually mild, treat with phototherapy

• Kidd, Duffy, Anti-U: Less common, variable severity

• **Lewis and I are IgM > do not cross placenta, no HDFN

Management of Isoimmunization

1. Test maternal ABO/RH and antibody screen

2. If screen positive, identify Ab

3. Test dad if possible > no antigen, no risk

4. Can test fetus for RhD, Kell, and Rhc with cfDNA, otherwise amnio

5. Monitor titers, if >1:16 then start MCA dopplers (much lower threshold for Kell, or any titer if previously affected pregnancy)

6. Monitor MCA Dopplers 16w to delivery

   1. MCA-PSV >1.5MOM = anemia

   2. Fetal transfusion possible, call MFM

   3. Can also give mom IVIG, plasmapheresis, or nipocalimab

7. Delivery timing:

   1. 37-38 weeks if no transfusion, stable titers, normal MCA

   2. If transfusion, 2-3 weeks after last one

8. Treatment for baby:

   1. Cord blood testing for Hgb, bile, blood type, and direct Coombs

   2. Phototherapy for hyperbilirubinemia

   3. IVIG

   4. Exchange transfusion

   5. Use irradiated blood

CPD vs Inadequate Contractions

Ultrasound Redating

How accurate is US for EFW?

Risk of ONTD + Folic acid dose

General population: 1/2500

Prior ONTD: 1/25

Folic acid: 400-800mcg starting 1 month before conception

Folic acid (twins): 1mg starting 1 month before conception

Folic acid for prior ONTD or high risk factors (prior ONTD, fam hx, DM, AEDs, thalassemias/hemoglobinopathies): 4mg starting 3 months before conception

**Continue to at least 12w GA

Weight gain in pregnancy

BMI = lbs/in² x 703 or kg/cm²

Underweight (<18.5) = 28-40

Normal weight (18.5-24.9) = 25-35

Overweight (25-29.9) = 15-25

Obese (>30) = 11-20

Twins = 37-54

APGAR and Cord Gases

APGAR (0-2 points each): Appearance, pulse, grimace, activity respiration

• 7-10 = Great

• 4-6 = Needs some help

• 0-3 = Critical

Cord gases: Arterial pH 7.24-7.27, PaCO2 50, PaO2 30-40, Base deficit <11-12

• Metabolic Acidosis: Low pH, high base deficit = usually due to tissue hypoxia

• Respiratory Acidosis: High pCO2 and normal base deficit = acute, transient umbilical cord compression or nuchal cord during delivery

• Mixed Acidosis: Low pH, high pCO2, significant base deficit = prolonged or severe impairment

• Critical Cutoffs: pH < 7.00 paired with a high base deficit (≥ 12 to 16 mmol/L) increases the risk of neonatal encephalopathy and serves as a major criterion for considering therapeutic hypothermia

DKA calculations

Anion Gap: Na⁺ - (Cl⁻ + HCO₃⁻), usually between 8 to 12 mEq/L

Corrected sodium:

• Add 1.6 mEq/dL for every 100 glucose over 100

• If Glucose >400, add 2.4mEq/dL

Blood Transfusion Components

• Packed rPBCs (1u = 300mL = 1u Hgb)

• Plt (1 pack = 250-300mL = 25-50K plt)

• FFP = many factors + vWF + antithrombin III (1u = 250mL)

• Cryo = fibrinogen + F8/12 + vWF + fibronectin (1u = 100-200mL = 100 fibrinogen)

Transfusion goals in hemorrhage/surgery/OB: Hgb >7-8, Plt 50K, fib 2K

• Fibrinogen very important for abruption, AFE, DIC

Massive transfusion protocol:

• Mimics whole blood

• 1 pRBC : 1 FFP : 1 Plt

Types of Blood Testing

• Type and screen: Determines ABO/Rh, screens for Abs

• Type and cross: Incubates pt blood with donor blood to ensure crossmatch, this blood is then set aside for the pt

  • Use for pt hx or anticipate hemorrhage/transfusion needs

  • Quickspin does this same process in 15 min if Abs in pt blood are neg

• New Ab screen required within 3 days for pregnant patient or non-pregnant pt with transfusion within 3 mo

Criteria for sIAI

Isolated maternal fever: 39C once or 38-39C x30min

sIAI: Maternal fever plus

1. Maternal leukocytosis

2. Purulent cervical drainage

3. Fetal tachycardia

Post-EDD Definitions

Post-dates: Unofficial term, usually post-EDD

Late term: 41.0 to 41.6

Post term: 42.0 or later

Monitoring Post-Dates Pregnancy

Continue weekly visits

Add NSTs 1-2x weekly with fluid check after 41weeks and recommend induction

After 42 weeks, strongly recommend delivery (IUFD rises to 3/1000)

Risks: IUFD, macrosomia, shoulder dystocia, meconium, postterm syndrome

PPD vs Baby Blues

Management of Cord Prolapse

1. Do not manipulate the cord

2. Elevate the fetal head

3. Maternal positioning: Hands and knees, Tberg

4. Don’t push, Terb if needed

5. If prolonged or need transport: Fill bladder, Sim’s position, keep cord warm and moist

Tocolytic MOA

Contraindications, Side effects, Dosage of major Tocolytics

Nifedipine:

• Loading dose: 20-10-10 q20min until ctx cease

• Maintenance: 20mg q8h

• Side effects N/V, flushing, dizziness. Causes hypotension, don’t use with heart conditions. Cannot combine with Mag.

Indomethacin:

• 50-100mg loading dose followed by 25mg q4-6h

• Side effects: GI upset, hypertension, plt dysfunction, PDA closure, oligo, fetal renal dysfunction, NEC/IVH in very premature babies.

• Avoid after 32 weeks. Contraindications include contraindications to NSAIDs.

Complications of Extreme Prematurity

Respiratory: RDS, bronchopulmonary dysplasia, apnea of prematurity

Neurological: IVH, periventricular leukomalacia, neurodevelopment deficits

CV: Patent PDA, hypotension, anemia, jaundice

GI: NEC, feeding intolerance, metabolic/endo issues

Immune: Sepsis

Sensory: Retinopathy of prematurity, hearing impairment

UTI/Pyelo Abx in preg

Most common bacterial: Proteus, E.Coli, Klebsiella

ASX Bacteriuria or UTI:

• Macrobid - Avoid in 1T (suggested increase risk of birth defects) or pyelo

• Keflex

• Bactrim - Avoid in 1T (folic acid depletion, birth defects) and 3T (jaundice, kernicterus)

• Fosfomycin - Avoid in pyelo

• Amox - High resistance

• Augementin - High resistance

If recurrent: Suppress with continuous or post-coital Macrobid or Keflex

Pyelo:

• Amp+gent

• CTX

• Cefepime

• Aztreonam

If not improving - kidney imaging.

After 24hr afebrile, transition to PO x2 weeks (not Macrobid or fosfomycin). Consider suppression and qT UCx for remainder of pregnancy.

Classic Triad of Neonatal Rubella

1. Sensorineural hearing loss

2. Cataracts, glaucoma, retinopathy

3. Patent PDA, pulmonary artery stenosis

4. Other: Low birth weight, microcephaly, intellectual disability, hepatosplenomegaly, and a "blueberry muffin" rash caused by extramedullary hematopoiesis

Wait 28 days after MMR to get pregnant (same as Varivax)!

AEDs in pregnancy

Best: Lamotrigine, levetiracetam

Also good: Oxcarbazepine, carbamazepine

No good: Valproate, topiramate, phenobarbital, phenytoin

Sickle cell gene

10% of African Americans, 0.3% of Caucasians